My wife and I first recorded Ceriagrion chaoi from the small lotus pond close to Upper Thomson Road in Bishan Park in 2007. Initially, it was misidentified as Ceriagrion auranticum. After close examination of a specimen collected from this pond and with the help of Matti Hämäläinen in September 2008, we confirmed that is was actually C. chaoi.
From mid-2010 to March 2012, Bishan Park, including the lotus pond, was closed for a major redevelopment. After the pond was reopened, I only managed to have one record of this species, made on 21 July 2012. I suspected that the drastic drop in population of C. chaoi was due to the removal of a row of trees on one side of the pond. Please refer to this article: https://everydaynature-tang.blogspot.com/2012/07/a-fenestrella-of-endau-rompin-c-chaoi.html
Today (20181206), I noticed that the fig tree on the other side of the pond had also disappeared. Without this tree, I believe C. chaoi couldn't survive in this site anymore. I frequented the pond in the months following my first sighting of C. chaoi. They were consistently seen to descend from the high branches of this fig tree at around 10 am and started their daily routine in the pond. The tree was obviously their roosting site for the night. With all the medium sized trees near the pond gone now, the site is not suitable for C. chaoi anymore. They are probably locally extinct at this site. There have been some other sites where nice species have disappeared due to habitat destruction/loss too, such as Indothemis limbata (Marina South) and Mortonagrion falcatum (Tuas). We need to understand the importance of urban ecology and know how to protect and enhance it.
When we observe rare dragonflies, it is a good idea to note down the environmental characteristics of the site and the insects' behaviour. The information may be useful for the future conservation of both the site and the insects.
Singapore is a city nation with much of her land urbanized. Yes, we do have nature reserves where habitats for wildlife are protected. However, the city areas also need nature's ecological services, which cannot be provided by just green spaces with trees, lawns and ornamental plants. Biodiversity in the green spaces is the key to a healthy ecosystem which provides ecological services such as keeping air fresh, preventing urban flooding and even producing food.
(20181207 update: I went to the pond again this morning. No sign of C. chaoi, as expected. In fact, the whole pond was quite lifeless, only a few individuals of Pseudagrion microcephalum and Neurothemis fluctuans could be seen, although it was 10 am and sunny. At around 10:15, a uniformed worker came and started spraying on the plants around the pond. I asked him what he was spraying. He answered he didn't know. He was just carrying out instructions. Whether it was fertilizer or pesticide, organic or not, it would negatively impact the ecology of the pond.
The ecology of the pond has suffered a double blow: the removing of the trees, and the spraying. The work of landscape contractors must be closely monitored! They often just care about the cost effectiveness of their operations, producing results which may look good on the surface, but devastating to the environment and ecology.)
From mid-2010 to March 2012, Bishan Park, including the lotus pond, was closed for a major redevelopment. After the pond was reopened, I only managed to have one record of this species, made on 21 July 2012. I suspected that the drastic drop in population of C. chaoi was due to the removal of a row of trees on one side of the pond. Please refer to this article: https://everydaynature-tang.blogspot.com/2012/07/a-fenestrella-of-endau-rompin-c-chaoi.html
Today (20181206), I noticed that the fig tree on the other side of the pond had also disappeared. Without this tree, I believe C. chaoi couldn't survive in this site anymore. I frequented the pond in the months following my first sighting of C. chaoi. They were consistently seen to descend from the high branches of this fig tree at around 10 am and started their daily routine in the pond. The tree was obviously their roosting site for the night. With all the medium sized trees near the pond gone now, the site is not suitable for C. chaoi anymore. They are probably locally extinct at this site. There have been some other sites where nice species have disappeared due to habitat destruction/loss too, such as Indothemis limbata (Marina South) and Mortonagrion falcatum (Tuas). We need to understand the importance of urban ecology and know how to protect and enhance it.
Singapore is a city nation with much of her land urbanized. Yes, we do have nature reserves where habitats for wildlife are protected. However, the city areas also need nature's ecological services, which cannot be provided by just green spaces with trees, lawns and ornamental plants. Biodiversity in the green spaces is the key to a healthy ecosystem which provides ecological services such as keeping air fresh, preventing urban flooding and even producing food.
(20181207 update: I went to the pond again this morning. No sign of C. chaoi, as expected. In fact, the whole pond was quite lifeless, only a few individuals of Pseudagrion microcephalum and Neurothemis fluctuans could be seen, although it was 10 am and sunny. At around 10:15, a uniformed worker came and started spraying on the plants around the pond. I asked him what he was spraying. He answered he didn't know. He was just carrying out instructions. Whether it was fertilizer or pesticide, organic or not, it would negatively impact the ecology of the pond.
The ecology of the pond has suffered a double blow: the removing of the trees, and the spraying. The work of landscape contractors must be closely monitored! They often just care about the cost effectiveness of their operations, producing results which may look good on the surface, but devastating to the environment and ecology.)
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| Worker spraying on plants 20181207, 10:15am |
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